Usual Apixaban Dosing OK With One Dose-Reduction Criterion

FRIDAY, July 29, 2016 (HealthDay News) -- For patients in the Apixaban for Reduction of Stroke and Other Thromboembolic Complications in Atrial Fibrillation (ARISTOTLE) trial, the 5 mg twice daily dose of apixaban is beneficial and appropriate for those with one dose-reduction criterion, according to a study published online July 27 in JAMA Cardiology.

John H. Alexander, M.D., from the Duke Clinical Research Institute in Durham, N.C., and colleagues analyzed data on 17,322 participants from the ARISTOTLE trial. Of patients with one or no dose-reduction criteria assigned to receive the 5 mg twice daily dose of apixaban or warfarin, 3,966 had one dose-reduction criterion.

The researchers found that patients with one dose-reduction criterion had higher rates of stroke or systemic embolism and major bleeding compared to those with no dose-reduction criteria. Similar benefits were seen for 5 mg twice daily apixaban versus warfarin on stroke or systemic embolism among patients with one (hazard ratio [HR], 0.94; 95 percent confidence interval [CI], 0.66 to 1.32) or no dose-reduction (HR, 0.77; 95 percent CI, 0.62 to 0.97) criterion (P for interaction = 0.36). Benefits were also similar for major bleeding (HRs, 0.68 [95 percent CI, 0.53 to 0.87] and 0.72 [95 percent CI, 0.60 to 0.86], respectively) (P for interaction = 0.71). Patterns were similar for each dose-reduction criterion and across the spectrum of age, body weight, and creatinine level and clearance.

"Patients with atrial fibrillation and isolated advanced age, low body weight, or renal dysfunction have a higher risk of stroke or systemic embolism and major bleeding but show consistent benefits with the 5 mg twice daily dose of apixaban versus warfarin compared with patients without these characteristics," the authors write. "The 5 mg twice daily dose of apixaban is safe, efficacious, and appropriate for patients with only one dose-reduction criterion."

Several authors disclosed financial ties to pharmaceutical companies, including Bristol-Myers Squibb and Pfizer, which manufacture apixaban and funded the study.